Vehicles with hybrid transmissions, that is to say with transmissions which permit the coupling of at least two motors as traction motors, have been proposed in a wide variety of embodiments. Such hybrid transmissions are known for example from the documents DE 11 2012 006 192, DE 10 2012 20 13 76 or from DE 10 2012 20 13 77. All architectures are based on the fundamental object of developing a hybrid transmission which constitutes an advantageous solution both with regard to the outlay in terms of construction and with regard to the possible functions and operating modes.
The present disclosure proposes a transmission arrangement for a vehicle which provides a wide variety of functions with low outlay in terms of construction. Embodiments of the disclosure emerge from the following description and from the appended figures.
The subject matter of the disclosure is a transmission arrangement, in particular a hybrid transmission arrangement for a vehicle. The vehicle may in particular be a passenger motor vehicle, heavy goods vehicle, bus etc. The transmission arrangement forms a part of the drive train and is designed to conduct a traction torque to driven wheels of the vehicle.
The transmission arrangement has a first input interface for the coupling of an internal combustion engine. The internal combustion engine optionally forms a part of the transmission arrangement. The internal combustion engine provides a traction torque for the vehicle. The input interface may be in the form of a real interface, or alternatively to this, the input interface is formed as a virtual or logical interface and is manifested for example as a shaft or the like.
The transmission arrangement furthermore has a second input interface for the coupling of an electric motor. The electric motor optionally forms a part of the transmission arrangement. The electric motor provides a traction torque for the vehicle. In particular, the electric motor is designed such that it alone can accelerate and/or propel the vehicle. The electric motor has a power of greater than 5 kilowatts, for example, and may be greater than 10 kilowatts. The second input interface may also be of real physical form, or alternatively to this, may form a virtual or logical interface, as has already been discussed with regard to the first input interface.
The transmission arrangement has a first planetary transmission section which has a first internal gear, a first planet carrier and a first sun gear as shafts. Furthermore, the first planetary transmission section may have a first set of planet gears, which are rotatably mounted on the first planet carrier. In particular, the first internal gear and/or the first sun gear meshes with the planet gears of the first set of planet gears. The internal gear, planet carrier and sun gear will hereinafter be referred to as shafts. The expression “shafts” may also be applied to a shaft that is static during operation. A first of the three shafts of the first planetary transmission section is operatively connected to the first input interface. The first shaft may be rotationally fixedly connected or at least rotationally fixedly connectable to the first input interface. A second shaft of the first planetary transmission section is operatively connected to the second input interface. The second shaft may be rotationally fixedly connected to the second input interface. The first planetary transmission section may be formed as a spur-gear planetary transmission section. The first internal gear, the planet gears and the first sun gear are formed as gears which are toothed in encircling fashion and/or on the face side.
Furthermore, the transmission arrangement has a second planetary transmission section which has a second internal gear, a second planet carrier, in particular with a second set of planet gears which are rotatably mounted on the second planet carrier, and a second sun gear as shafts. The shafts may be formed as rotating or static shafts. A first shaft of the second planetary transmission section is operatively connected and may be rotationally fixedly connected to the first input interface. A second shaft of the second planetary transmission section is operatively connected and may be rotationally fixedly connected to the second input interface.
The main axes of the first and of the second planetary transmission section and/or axes of rotation of the sun gears of the first and of the second planetary transmission section are arranged so as to be parallel and offset with respect to one another.
The transmission arrangement furthermore has a first speed ratio transmission section, which provides at least one first speed ratio stage. The first speed ratio transmission section may provide two, three or more speed ratio stages. The speed ratio may be any desired speed ratio; in particular, it is also possible for a speed reduction to be implemented by means of the speed ratio transmission section. A third shaft of the first planetary transmission section is operatively connected to an input of the first speed ratio transmission section. The third shaft of the first planetary transmission section may be rotationally fixedly connected to the input of the first speed ratio transmission section.
Furthermore, the transmission arrangement has a second speed ratio transmission section. The second speed ratio transmission section has at least one second speed ratio stage, and may have a multiplicity of second speed ratio stages. The third shaft of the second planetary transmission section is operatively connected, in particular rotationally fixedly connected, to an input of the second speed ratio transmission section.
Furthermore, the transmission arrangement has an output interface. The outputs of the speed ratio transmission sections are operatively connected to the output interface.
It is thus possible for a traction torque to be conducted into the transmission arrangement via the input interfaces and to be conducted out via the output interface. For example, the output interface may be adjoined by an output transmission stage, in particular a final drive, and/or a differential device for distributing the transmitted traction torque to axles of the vehicle or to wheels of a driven axle. The output transmission stage and/or the differential device optionally form a part of the transmission arrangement.
In the context of the disclosure, it is proposed that the transmission arrangement has a coupling section for the coupling of the second shafts of the planetary transmission sections. The second shafts are in particular supported against one another via the coupling section in at least one operating mode.
Here, it is a consideration of the disclosure that advantageous operating modes can be set in the transmission arrangement if the second shafts act counter to one another in at least one operating mode. In this way, a deceleration and/or braking torque is introduced into the second shafts owing to the mutual support. Examples of such advantageous operating modes will be discussed in more detail below.
It may be provided that the coupling section is formed and/or arranged such that, in the case of a co-directional torque at the first shafts of the two planetary transmission sections and a co-directional torque at the third shafts of the planetary transmission sections, the torques at the second shafts act in opposite directions. The mutual support is realized as a result of the action in opposite directions. Alternatively, opposite torques prevail at the first shafts and opposite torques prevail at the third shafts and opposite torques prevail at the second shafts.
In one possible design embodiment of the disclosure, the coupling section is formed as a transmission section with a negative speed ratio. As a result of the negative speed ratio, a direction of rotation reversal occurs in the transmission section, such that the second shafts can be supported against one another in the at least one operating mode.
In principle, it may be provided that a deceleration torque and/or a braking torque is applied to at least one of the second shafts by means of the electric motor, which likewise acts on the second shafts via the second input interface. The transmission arrangement may have a coupling brake device. The coupling brake device acts on the coupling section. In particular, the coupling brake device decelerates at least one of the second shafts or both second shafts in relation to a frame or a housing of the transmission arrangement. In this way, it is possible for the coupling section to be set into a rigid state and/or blocked, such that the second shafts cannot be rotated relative to one another.
In one possible embodiment of the disclosure, it is provided that the coupling brake device acts on the second input interface. In particular, the brake device is rotationally fixedly connected to a brake side of the second input interface.
In an alternative embodiment of the disclosure, it is provided that the coupling brake device acts on the second shaft of the first and/or of the second planetary transmission section. By virtue of the fact that the second shafts of the first and of the second planetary transmission sections are coupled to one another via the coupling section, it is sufficient for only one of the second shafts to be braked.
In an example design embodiment of the disclosure, the first shaft of the first planetary transmission section is formed as the first internal gear, the second shaft of the first planetary transmission section is formed as the first sun gear, the third shaft of the first planetary transmission section is formed as the first planet carrier. Alternatively or in addition, the first shaft of the second planetary transmission section is formed as the second internal gear, the second shaft of the second planetary transmission section is formed as the second sun gear, and the third shaft of the second planetary transmission section is formed as the second planet carrier. In this embodiment, it is firstly necessary for the fixed-carrier speed ratios of the planetary transmission sections to be set in accordance with the application, and it is secondly the case that a compact construction is possible.
In an example embodiment, the transmission arrangement has at least or exactly one output-side coupling actuator apparatus, which includes the coupling brake device. Inputs of the output-side coupling actuator apparatus are operatively connected, in particular rotationally fixedly connected, to the second and to the third shaft of one of the planetary transmission sections, that is to say the first or the second planetary transmission section. The output-side coupling actuator apparatus is designed to rotationally fix the second and the third shaft to one another, such that these can rotate conjointly if appropriate. In an alternative shift state, the output-side coupling actuator apparatus is designed to rotationally fix the second shaft with respect to a frame and in particular a housing of the transmission arrangement and thus form the coupling brake device. Further operating modes of the transmission arrangement can be set by means of the output-side coupling actuator apparatus.
Alternatively or in addition, the transmission arrangement has at least one input actuator apparatus. The input actuator apparatus is arranged between the first input interface and the first shaft of one of the planetary transmission sections. The transmission arrangement optionally has two input actuator apparatuses, such that an input actuator apparatus is connected upstream of each of the first shafts. The input actuator apparatus is designed to rotationally fix the first input interface to the first shaft, and alternatively rotationally fix the first shaft with respect to a frame.
Both the output-side coupling actuator apparatus and the input actuator apparatus may also, as optional operating states, assume a neutral state. The inputs of the coupling actuator apparatus and of the input actuator apparatus are shifted independently of one another.
A further possible embodiment of the disclosure relates to a transmission arrangement which has an input actuator apparatus upstream of one of the planetary transmission sections and a clutch device upstream of the other planetary transmission section. This transmission arrangement furthermore includes first and second input-side coupling actuator apparatuses. The first input-side coupling actuator apparatus has the first shaft and the second shaft of the first planetary transmission section as inputs. In a first shift state, the first and the second shaft are rotationally fixable to one another. In a second shift state, the second shaft runs freely, and the first shaft is rotationally fixedly coupled to a frame, in particular to a housing of the transmission arrangement. Furthermore, the first input-side coupling actuator apparatus can assume a neutral state, wherein both shafts and/or inputs run freely. The second input-side coupling actuator apparatus has the first shaft and the second shaft of the second planetary transmission section as inputs. In a first shift state, the first and the second shaft are rotationally fixable to one another. In a second shift state, the first shaft runs freely, and the second shaft is rotationally fixedly coupled to a frame, in particular to a housing of the transmission arrangement. Furthermore, the second input-side coupling actuator apparatus can assume a neutral state, wherein both shafts and/or inputs run freely.
A further possible subject matter relates to a vehicle having the transmission arrangement as described above.